Posted
by
Zonk
on Saturday October 28, 2006 @01:35AM
from the wet-but-no-cigar dept.

DestroyAllZombies writes "More news about Mars. The good news: New Scientist reports that more analysis of Rover data supports the claims for widespread oceans in Mars' distant past. The bad news, from the article: 'An ocean of water once wrapped around Mars, suggests the discovery of soil chemicals by NASA's rovers. But the same chemicals also indicate that life was not widespread on the planet at the time the ocean was present.'"

Why is it bad news to learn that there was never any life on Mars? Wouldn't it be much worse news to learn that life was common there and was utterly wiped out?I think most people would agree that a planet-wide extinction of all life would qualify as 'bad news'.

Neither is good news or bad news. Science exists to quantify and explain, not to hope for something. If hope that life existed on Mars is the major reason for your research, you aren't being a scientist. You are being a cheerleader.

If hope that life existed on Mars is the major reason for your research, you aren't being a scientist.

Scientists are human and are allowed to have motivations. They shouldn't let it bias their work, of course, but still. If hope for finding something interesting and exciting got them into science, and keeps them at it, that's fine.
Also, who restricted this to scientists? You don't have to be a scientist to be interested in whether there had been life on mars or not.
I think the way "bad" is used in

Neither is good news or bad news. Science exists to quantify and explain, not to hope for something. If hope that life existed on Mars is the major reason for your research, you aren't being a scientist. You are being a cheerleader.

Wrong. Anyone who uses scientific method in his research is a scientist. It doesn't matter if he's motivated by dreams of going Kirk with alien females, or gets his kicks from abstract knowledge; purity of motive is irrelevant. The only requirement is the application of scien

I think the crowd here wants to live in a SF universe. I for one, would like to see a contact with an alien civilization in my lifetime, even if I think it is improbable. A Big Question in science is : Is the apparition of life on Earth a common event in the Universe or is it a unique and almost impossible event ?

Having proofs of ancient life on Mars would have put us a step nearer the alien contact. Of course the crowd here is mostly optimistic about aliens intentions:-)

"A Big Question in science is : Is the apparition of life on Earth a common event in the Universe or is it a unique and almost impossible event? "

Is that really such a question? Given that there are a bazillion (heh, scientific, I know) planets out there, there's a huge number of Earthlikne planets as well, making it likely that there is something similar elsewhere life-wise. Also, once we look past our "Star Trek" prejudices, there's the likelihood of even more different types of life in a variety of ot

"The Star Trek universe is actually filled with non-humanoid life; it's just that humans tend to make contact with humanoid life and not interact much with any other life forms."

I thought of mentioning that, but figured I'd leave it at the more superficial level of Trek, rather than deep Trekkiedom. You know, where the public knows "Star Trek" as a show where starships travel around the galaxy and interact for the most part with aliens that are nothing other than humans with forehead bumps.

A bazillion may not be enough, it is not infinite. It is all about the probability of the apparition of life. If the apparition of life on a earth-like planet has a probability of 1/X and there are less than X planets in the universe, then we probably are alone, and maybe it has taken several universes for the life to appear. Big numbers can exist on the two sides of the equation. We simply don't have enough data yet to know

You know that life is extinct on Mars? That would mean that you are the only person on this planet who knows that. The answer is that we do not know if Life does or does not exists on Mars. In fact, I think that we will never know until we go there. The problem is that somebody develops a test and once it is positive, another person will come up with a reason why it is inorganic in nature. That makes us back to square one. The issue is that it costs a lot of money to send up a multi-test machine AND will ha

I'm pretty sure there are a few microbes in spore form on Mars: the first few missions we weren't too careful about not contaminating our probes, and so there have been stow-away bacteria on mars (from Earth). I doubt that life has thrived, given the harsh conditions. In fact, they will almost certainly eventually die out and become extinct unless we send more or go down there and change the environment.

In the source piece, we see oceans loaded with phosphates - which come from laundry detergents. So not only was there life on Mars but they were the worst kind of neat-freaks, ones that are environmentally irresponsible. You want contact with these jerks? Get a life!

Water on earth tends to get "recycled" constantly: sea water evaporates makes clouds which make rain which eventually gets into rivers which go back out to the ocean etc. If Mars was covered with water, where did this water go?

Mars doesn't have the same gravity that the Earth does, nor does it have a magnetic field to stop incoming solar wind. The water could have evaporated, and since it is a lighter element (than CO2, which is most of Mars' atmosphere) it could have just blown away.

This is a function of having a molten core, if there is moving metal, there is a magnetic field (which Mars doesn't have much of now, but it does have a weak one, probably residual from a time when there was a molten core). So, once upon a time, Mars did have a magnetic field, and that helped keep the water there.

This is a function of having a molten core, if there is moving metal, there is a magnetic field

Couldn't that weak field be the residual of one dissapearing or the beginnings of one forming around Mars as a result of a Geomagnetic reversal? Is there definite proof that Mars doesn't have a molten core? Or are we assuming because it has no field?

Couldn't that weak field be the residual of one dissapearing or the beginnings of one forming around Mars as a result of a Geomagnetic reversal?

Sure, it is possible, but the field that is there is very weak (on the order of 1/100th of Earth's, if memory serves). Since we have only been measuring the magnetic field of Mars for the last 9 years (thanks to Mars Global Surveyor) there isn't the same long term magnetic data to compare with that of the Earth.

Mars doesn't have the same gravity that the Earth does, nor does it have a magnetic field to stop incoming solar wind. The water could have evaporated, and since it is a lighter element (than CO2, which is most of Mars' atmosphere) it could have just blown away.

So does that mean Earth is just loosing H2O more slowly than did Mars? Comforting, sort of.

But I get a kick out of astro-science. We know so little about the universe it isn't funny. We assume the universe is growing, while it may be that we are

Any number of places. A lot of it might be trapped as ice or hydrate crystals underground. At least some of it is frozen at the north and south poles. And as others have noted, Mars has significantly lower gravity than earth (approximately 1/3 gee acceleration at the surface), which significantly impedes its ability to hold an atmosphere (which holds water), and additionally lacks a magnetosphere (through not being geologically active, a metallic core surrounded by liquid layers is necessary for one) whi

But the same chemicals also indicate that life was not widespread on the planet at the time the ocean was present.

Whoa whoa whoa... how is that bad news? We're not looking for widespread life, we're looking for life. In general. Any. At all. That sentence implies that there was life, just it wasn't widespread. I think that should have been reworded.

But disregarding that, just because there was a lot of phosphorus in the water doesn't mean that life couldn't exist there. It just means life identical to the structure of life on earth couldn't exist there. Who's to say that life has to be built just the way it is on earth?

actually i was reading a post by a pathologist a while ago concerning the fear of alien bacteria, and it's something of a misconception.
it's actually very very likely that our bodies will be deadly to any alien life. example.
can humans survive on mars unaided? no? so it means anything thats suited to the conditions on mars will die if exposed to our own viable conditions.
interesting stuff i never thought it but it's quite obvious when you think it through.

I think that's a very good point to make against concerns of some sudden horrible epidemic, but I think there/is/ some potential for concern when it comes to people trying to live somewhere alien long-term. While it's likely we would kill all manner of alien life on contact to start with, sticking around would provide all sorts of opportunities for lifeforms to adapt. Rather than just having a stark difference between our conditions and theirs, there would be border areas, say, between our living space and

But disregarding that, just because there was a lot of phosphorus in the water doesn't mean that life couldn't exist there. It just means life identical to the structure of life on earth couldn't exist there. Who's to say that life has to be built just the way it is on earth?

Physics and chemistry says there is only a strictly limited series of chemical reactions that can drive life - and only a strictly limited series of enviroments where it can arise. (Yes, I know about the various extremeophiles here on

Physics and chemistry say no such thing. Biology used to say things like that, then started to find out how wrong it was. Nobody knows which extremophiles are colonists and which ones are the originals who left to colonize other places, like the surface.Physics and chemistry point out some things that probably won't work, and a few possibilities for others that could. There's a lot around the outside that we simply won't know about until we find it though.

Um... yes, they do. You won't for example find a life form based on a Helium/Uranium reaction. Or any one of thousands of of other possible reactions. (For example it's impossible to base life around endothermic reactions - there has to be some exothermic reactions.)

Biology used to say things like that, then started to find out how wrong it was. Nobody knows which extremophiles are colonists and which ones are the originals who left to colonize ot

Please. We don't even know that the fuck life even is, every year they come out with a new god damn definition. And this definition as such is based fully on life we've seen on earth. Who's to say that there can't be sentient "ghost" beings that are made out of a carbon/oxygen combination? Just because I can't easy recognize the fact that they are living doesn't mean they aren't. It just means we don't know what we're really even looking for.

You are somewhat correct, physics and chemistry suggest that certain reactions are more likely to form life than others. That still leaves a lot of others that might, only a subset of which are used by life as we know it. That leaves a bunch of others that could be used by life-as-we-don't-know-it. While your original post didn't explicitly say it, in context you were certainly implying that chemistry and physics pretty much rule out anything but life as we know it. You know we don't even have a really

From what? Nuclear reactions? The very point is that they think that the amounts found here are consistent with inorganic extraction from minerals. You can of course stipulate that the conditions that made those reactions favorable were created by life, but there is nothing that indicates that. If there was life with a different chemistry, the current results make it just as likely that this form of life was indifferent to phosporus.

BUT, there is no way we are going to find intelligent life in this galaxy, and life itself is going to be rare.To understand why, consider the galaxy is only about 100,000 light years across. Super intelligent species are super intelligent because they crossed biological distances, and the same forces will cause them to cross galactic distances and explore.

some may say 100K light years is so large as to be impossible to explore. But consider this idea. What these civilizations will do is create cell size

I think the most plausible explanation is that simple life (RNA or equivalent) may be common, but complex life (DNA or equivalent) is very rare. Considering all the things we don't know, though, any particular explanation at this point is probably wrong.

Looks like this is exactly what I was arguing:). Thanks for pointing it out. One thing I don't see though is the following idea.What are the chances there are just several (2, 3, 4) intelligent life forms in the Galaxy? I think the chances of this are very low. I believe 1 intelligent life form is much more likely than 2, 3 or 4, and I also think that many intelligent life forms in the galaxy is more likely than a small number. Given many intelligent life forms, it would seem one of them would seek us

There is no problem with the hypothesis that our galaxy has plenty of intelligent life in it but at the same time there is no contact yet between them and us:1) the amount of time that humans exist on Earth is every small. Our recorded history is in the range of 10000 years, which is a very small amount of time, in cosmic terms, for other intelligent lifeforms to find us.

2) we have been sending radio signals to space for almost 100 years now. Considering the direction and width of radio emissions, the chanc

I too never spoke about "biological progress means we will be able to explore the galaxy"...you mentioned it.The fact remains that neither the pessimistic view or the optimistic view can be regarded as established: we simply do not know (and can not presently know) what has happened in the rest of the galaxy or the universe.

Personally I go with the optimistic view, because it is more logical than the pessimistic view: if God does not exist and Earth is the creation of chaotic processes (orders does come out

Life could of existed on mars from my perspective. Remember folks, when the planets are formed, it is hot and there is lots of whirling gases and splashing seas of unknown chemicals at a certain point. The surface is hot and like a rock at first but mars has red dirt and sands like the ones found in zacatecas, mexico. Dirt just doesnt form after rock formation.
Around the area where a sea should of been, you should see sands and not dirt. around where you see dirt, you should see dirt, not sands. Sand

Intelligent life springs up everywhere. Then they discover television or its equivalent. Shortly thereafter, they amuse themselves to death(apologies to Roger Waters.) If you disagree, cancel your cable subscription and spend the next couple of months watching only network tv.